Thermal module and method of manufacturing same

ABSTRACT

A thermal module and a method of manufacturing same are disclosed. The thermal module includes a radiating fin assembly and a base. The base has a bottom and a plurality of slot vertically extending through the base in a thickness direction thereof. The radiating fin assembly includes a plurality of radiating fins, each of which has a heat-dissipation end and a heat-absorption end. The heat-absorption ends are correspondingly extended through the slots and bent to bear on the bottom for contacting with a heat-producing element. Heat produced by the heat-producing element is absorbed by the heat-absorption ends and directly transferred from the heat-absorption ends to the heat-dissipation ends without the problem of thermal resistance. Therefore, upgraded heat transfer efficiency and excellent heat dissipation effect can be achieved with the thermal module.

This application clams the priority benefit of Taiwan patent applicationnumber 100106354 filed on Feb. 25, 2011.

FIELD OF THE INVENTION

The present invention relates to a thermal module and more particularlyto a thermal module capable of reducing thermal resistance toeffectively upgrade heat transfer efficiency thereof. The presentinvention also relates to a method of manufacturing the above thermalmodule.

BACKGROUND OF THE INVENTION

In the present computer-related industrial fields, a passive-type heatsink is usually tightly attached to a heat-producing surface of anelectronic element, such as a central processing unit (CPU), a south andnorth chip set, etc., so that the produced heat can be effectivelycarried away from the electronic element to dissipate into ambient air,ensuring the heat-producing electronic element to operate at a properworking temperature.

Conventionally available heat sinks can be generally divided into twotypes, namely an integral heat sink and an assembled heat sink. Theintegral heat sink mainly has a base, one side of which is in directcontact with a heat source and the other side of which is formed into aplurality of outward extended radiating fins for radiating heat absorbedby the base into ambient air. The assembled heat sink 1, as shown inFIGS. 1A and 1B, includes a base 10 and a plurality of radiating fins 12assembled to the base 10. The base 10 is formed with a plurality ofslots 101 sunken into an upper side of the base 10 for the radiatingfins 12 to correspondingly insert therein. A lower side of the base 10is in contact with a heat-producing element 14, such as a CPU or a southand north bridge chipset, for absorbing the heat produced by theheat-producing element 14.

Each of the radiating fins 12 has a heat-absorption end 121 and aheat-dissipation end 122 extended from the heat-absorption end 121. Theheat-absorption ends 121 of the radiating fins 12 are correspondinglyheld in the slots 101, so that the base 10 and the radiating fins 12together form the heat sink 1. When the heat-producing element 14produces heat, the base 10 absorbs the produced heat and guides theabsorbed heat to the heat-absorption ends 121 correspondingly held inthe slots 101, and then the heat-absorption ends 121 further transferthe received heat to the heat-dissipation ends 122, from where the heatis radiated into ambient air and diffused.

While the two types of conventional heat sinks all can achieve thepurpose of carrying heat away from the heat-producing element 14, theydo not provide good heat dissipation effect. This is because the heatproduced by the heat-producing element 14 is first transferred to thebase 10 and then indirectly transferred to the radiating fins 12 via thebase 10. Thermal resistance tends to occur during the process oftransferring the heat from the base 10 to the radiating fins 12 tothereby result in lowered heat transfer efficiency and accordingly poorheat dissipation effect.

In conclusion, the conventional heat sinks have the followingdisadvantages: (1) having low heat transfer efficiency; (2) indirectheat transfer from the heat source via the base to the radiating finscausing the problem of thermal resistance; and (3) providing poor heatdissipation effect.

It is therefore tried by the inventor to develop an improved thermalmodule that eliminates the drawbacks in the conventional heat sinks toprovide upgraded heat transfer efficiency and excellent heat dissipationeffect.

SUMMARY OF THE INVENTION

A primary object of the present invention is to provide a thermal modulecapable of reducing thermal resistance to enable upgraded heat transferefficiency thereof.

Another object of the present invention is to provide a thermal moduleproviding excellent heat dissipation effect.

A further object of the present invention is to provide a method ofmanufacturing a thermal module capable of reducing thermal resistance toenable upgraded heat transfer efficiency thereof.

A still further object of the present invention is to provide a methodof manufacturing a thermal module capable of providing excellent heatdissipation effect.

To achieve the above and other objects, the thermal module according tothe present invention includes a base having a plurality of slots and abottom, the slots vertically extending through the base in a thicknessdirection thereof; and a radiating fin assembly having a plurality ofradiating fins, each of the radiating fins having a heat-dissipation endand a heat-absorption end extended from the heat-dissipation end. Theheat-absorption ends of the radiating fins are respectively extendedthrough the slots to downward project from the base, and the downwardprojected heat-absorption ends are bent to bear on the bottom of thebase, so that the base and the radiating fin assembly are associatedwith one another to form an integral unit to complete the thermalmodule. With the above arrangements, the heat-absorption ends are indirect contact with a heat-producing element to absorb the heat producedby the latter, and the absorbed heat is directly guided from theheat-absorption ends of the radiating fins to the heat-dissipation endsfor dissipation. In this manner, it is able to effectively reduce thethermal resistance and increase an overall heat transfer efficiency ofthe thermal module for the same to provide excellent heat dissipationeffect.

To achieve the above and other objects, the method of manufacturingthermal module according to the present invention includes the followingsteps: providing a base having a plurality of slots vertically extendingthrough the base in a thickness direction thereof, and a plurality ofradiating fins; correspondingly extending the radiating fins through theslots, so that the radiating fins respectively have one end downwardprojected from the base; and bending the downward projected ends of theradiating fins for them to bear on a bottom of the base to complete thethermal module. With this method, the manufactured thermal module canhave effectively reduced thermal resistance and upgraded heat transferefficiency to achieve excellent heat dissipation effect.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present inventionto achieve the above and other objects can be best understood byreferring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein

FIG. 1A is a schematic assembled perspective view of a conventional heatsink;

FIG. 1B is a vertical sectional view of FIG. 1A;

FIG. 2A is a schematic assembled perspective view of a thermal moduleaccording to a first preferred embodiment of the present invention;

FIG. 2B is a schematic assembled perspective view of a variant of thethermal module according to the first preferred embodiment of thepresent invention;

FIG. 3 is a vertical sectional view of FIG. 2A;

FIG. 4 is an exploded perspective view of the thermal module accordingto the first preferred embodiment of the present invention;

FIG. 5 is a flowchart showing the steps included in a method ofmanufacturing the thermal module according to the first preferredembodiment of the present invention;

FIG. 6 is an assembled perspective view of a thermal module according toa second preferred embodiment of the present invention;

FIG. 7 is a vertically sectioned perspective view of the thermal moduleof FIG. 6; and

FIG. 8 is an exploded perspective view of the thermal module accordingto the second preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described with some preferredembodiments thereof and with reference to the accompanying drawings. Forthe purpose of easy to understand, elements that are the same in thepreferred embodiments are denoted by the same reference numerals.

Please refer to FIGS. 2A, 3 and 4, in which a thermal module 2 accordingto a first preferred embodiment of the present invention is shown. Asshown, the thermal module 2 includes a base 21 and a radiating finassembly 22. The base 21 has a plurality of slots 211 and a bottom 213.The slots 211 are formed on the base 21 to respectively verticallyextend through the base 21 in a thickness direction thereof. In FIG. 2A,the slots 211 are parallelly and equally spaced on the base 21.Alternatively, according to a variant of the first preferred embodimentas shown in FIG. 2B, the slots 211 can also be parallelly butnon-equally spaced on the base 21.

The radiating fin assembly 22 includes a plurality of radiating fins221, each of which has a heat-dissipation end 223 and a heat-absorptionend 224. The heat-dissipation ends 223 of all the radiating fins 221together define a heat-dissipation section 226, at where heat absorbedby the radiating fins 221 is dissipated into ambient air through heatexchange between the radiating fin assembly 22 and the ambient air. Theheat-absorption ends 224 of the radiating fins 221 are correspondinglyextended through the slots 211 to downward project from the base 21, andthe downward projected heat-absorption ends 224 are mechanically bent byway of, for example, rolling or stamping to thereby tightly bear on thebottom 213 of the base 21, so that the radiating fins 221 are firmlyassociated with the base 21 to form an integral unit to complete thethermal module 2.

Please refer to FIGS. 2A and 3. As can be seen from FIG. 3, theheat-absorption ends 224 downward projected from the slots 211 afterbending are oriented perpendicular to the heat-dissipation ends 223 ofthe radiating fins 221; and the bent heat-absorption ends 224 of theradiating fins 221 together define a heat-absorption section 227 forbearing on a heat-producing element 3, such as a CPU, a south and northbridge chipset, a graphics chip or other heat source, to absorb heatproduced by the heat-producing element 3, so that the absorbed heat isdirectly transferred from the heat-absorption section 227 to theheat-dissipation section 226 for diffusing and dissipating into ambientair.

With the design of the present invention, the absorbed heat is directlyguided from the heat-absorption section 227 of the radiating fins 221 tothe heat-dissipation section 226 for dissipation. In this manner, it isable to effectively reduce the thermal resistance and increase anoverall heat transfer efficiency of the thermal module for the same toprovide excellent heat dissipation effect.

Please refer to FIGS. 3 and 5 at the same time. FIG. 5 is a flowchartshowing the steps included in a method of manufacturing the thermalmodule 2 according to the first preferred embodiment of the presentinvention.

In a first step 200, the manufacturing process starts.

In a second step 201, a base having a plurality of slots, and aplurality of radiating fins are provided.

More specifically, a base 21 having a plurality of slots 211 as well asa plurality of radiating fins 221 are provided. The slots 211 verticallyextend through the base 21 in a thickness direction thereof, and can beparallelly arranged on the base 21 to equally space from one another, asshown in FIG. 2A, or to non-equally space from one another, as shown inFIG. 2B.

In a third step 202, the radiating fins are correspondingly extendedthrough the slots to downward project their respective one end from thebase.

More specifically, the radiating fins 221 are correspondingly extendedthrough the slots 211 for their respective one end, i.e. theheat-absorption end 224, to downward project from the bottom 213 of thebase 21.

And, in a fourth step 203, the ends of the radiating fins downwardprojected from the base are bent to bear on the bottom of the base.

More specifically, the heat-absorption ends 224 of the radiating fins221 downward projected from the base 21 are mechanically bent by rollingor stamping for them to tightly bear on the bottom 213 of the base 21,so that the base 21 and the radiating fins 221 are associated with oneanother to form an integral unit to complete the thermal module 2.

When the thermal module 2 manufactured in the above-described method isused to carry heat from the heat-producing element 3, the occurrence ofthermal resistance can be effectively avoided to enable a largelyupgraded overall heat transfer efficiency and accordingly, excellentheat dissipation effect.

FIGS. 6, 7 and 8 illustrate a thermal module 2 according to a secondpreferred embodiment of the present invention. The thermal module 2 inthe second preferred embodiment includes a base 21, a radiating finassembly 22 having a plurality of radiating fins 221, and at least oneheat pipe 26. Since the connection manner of the radiating fins 221 tothe base and the structure of the radiating fin assembly 22 aregenerally similar to that in the first preferred embodiment, they arenot repeatedly described herein. In the second preferred embodiment, thebase 21 further has a plurality of coupling slots 24 and at least onedownward opened recess 25. The coupling slots 24 are formed on the base21 at locations between the slots 211 and outer sides of the base 21 forcorresponding heat-absorption ends 224 to insert therein and accordinglybe held thereto to assist in holding the radiating fins 221 in place.The recess 25 is formed on the bottom 213 and communicates with theslots 211, and the heat-absorption ends 224 are bent to bear on an innerwall surface of the recess 25.

While the illustrated second preferred embodiment are shown with fourrecesses and four heat pipes 26, it is understood the number of the heatpipes 26 and of the recesses 25 is not necessarily limited to four. Inpractical implementing of the present invention, a user may determinethe number of the recesses 25 and of the heat pipes 26 according to theactually available heat dissipation space and the required heatdissipation effect.

Please refer to FIG. 7 along with FIG. 8. Each of the heat pipes 26includes a vaporizing end 261 and a condensing end 262. The condensingends 262 are extended through the heat-dissipation section 226 of theradiating fin assembly 22. More specifically, the condensing ends 262are parallelly extended at respective one end through theheat-dissipation ends 223. The vaporizing ends 261 are correspondinglyfixed in the recesses 25. Each of the vaporizing ends 261 has a firstside 2611 tightly bearing on the heat-absorption ends 224, i.e. theheat-absorption section 227, and a second side 2612 opposite to thefirst side 1611 for contacting with the heat-producing element 3.

When the heat-producing element 3 produces heat, the vaporizing ends 261of the heat pipes 26 absorb the heat and transfer the absorbed heat tothe condensing ends 262, and the condensing ends 262 in turn transferthe received heat to the heat-dissipation section 226 being extendedthrough by the condensing ends 262, so that the heat transferred to theheat-dissipation section 226 is radiated from the heat-dissipation ends223 of the radiating fins 221 into ambient air. Meanwhile, theheat-absorption section 227 would also absorb part of the heat producedby the heat-producing element 3, and the heat absorbed by theheat-absorption section 227 is directly transferred to theheat-dissipation section 226 for dissipating into ambient air throughheat exchange between the air and the radiating fins 221. Therefore, thethermal module 2 according to the second preferred embodiment of thepresent invention provides double heat-absorption effect and avoids theproblem of thermal resistance to thereby enable upgraded overall heattransfer efficiency and excellent heat dissipation effect.

In brief, compared to the conventional thermal modules, the presentinvention has the following advantages: (1) enabling upgraded heattransfer efficiency; (2) avoiding the occurrence of thermal resistance;and (3) providing excellent heat-dissipation effect.

The present invention has been described with some preferred embodimentsthereof and it is understood that many changes and modifications in thedescribed embodiments can be carried out without departing from thescope and the spirit of the invention that is intended to be limitedonly by the appended claims.

1. A thermal module, comprising: a base having a plurality of slots anda bottom, the slots vertically extending through the base in a thicknessdirection thereof; and a radiating fin assembly having a plurality ofradiating fins, each of the radiating fins having a heat-dissipation endand a heat-absorption end; the heat-absorption ends of the radiatingfins being respectively extended through the slots to downward projectfrom the base, and the downward projected heat-absorption ends beingbent to bear on the bottom of the base.
 2. The thermal module as claimedin claim 1, wherein the heat-absorption ends after bending are orientedperpendicular to the heat-dissipation ends of the radiating fins.
 3. Thethermal module as claimed in claim 1, wherein the heat-absorption endsof the radiating fins together define a heat-absorption section.
 4. Thethermal module as claimed in claim 1, wherein the heat-dissipation endsof the radiating fins together define a heat-dissipation section.
 5. Thethermal module as claimed in claim 3, wherein the heat-absorptionsection bears on a heat-producing element for absorbing heat produced bythe heat-producing element.
 6. The thermal module as claimed in claim 1,wherein the slots are parallelly arranged on the base to equally spacefrom one another.
 7. The thermal module as claimed in claim 1, whereinthe slots are parallelly arranged on the base to non-equally space fromone another.
 8. The thermal module as claimed in claim 1, wherein thebase is further provided at locations between the slots and outer sidesof the base with a plurality of coupling slots, and at the bottom withat least one downward opened recess; the recess being communicable withthe slots, and the heat-absorption ends downward projected from the basebeing bent to bear on an inner wall surface of the at least one recess.9. The thermal module as claimed in claim 8, further comprising at leastone heat pipe having a vaporizing end and a condensing end; thevaporizing end being correspondingly fitted in the recess, and having afirst side tightly bearing on the heat-absorption ends of the radiatingfins and a second side contacting with a heat-producing element; and thecondensing end being extended through the heat-dissipation ends of theradiating fins.
 10. A method of manufacturing thermal module, comprisingthe following steps: providing a base having a plurality of slots, and aplurality of radiating fins; and the slots vertically extending throughthe base in a thickness direction thereof; correspondingly extending theradiating fins through the slots, so that the radiating finsrespectively have one end downward projected from the base; and bendingthe downward projected ends of the radiating fins for them to bear on abottom of the base.
 11. The thermal module manufacturing method asclaimed in claim 10, wherein the downward projected ends of theradiating fins are mechanically bent to bear on the bottom of the base.12. The thermal module manufacturing method as claimed in claim 11,wherein the downward projected ends of the radiating fins aremechanically bent in a manner selected from the group consisting ofrolling and stamping.
 13. The thermal module manufacturing method asclaimed in claim 10, wherein the slots are parallelly formed on the baseto equally space from one another.
 14. The thermal module manufacturingmethod as claimed in claim 10, wherein the slots are parallelly formedon the base to non-equally space from one another.